ISDN Telephones

A translation into integrated digital networks is possible. ISDN Telephone enables various applications, such as data transmission via circuit switching. Other possibilities include packet-switched data transmission as well as telex and teletext. The digital technology has completely replaced the analogue exchange. This has resulted in increased performance and a doubling of connection lines.

The differences between ISDN Telephone and analogue connections

The main difference between ISDN Telephone and the analogue connection lies in the digital transmission to the end device. This allows multiple channels to be transmitted simultaneously over a telephone connection. The ISDN basic connection has two channels, which can be used separately for data transmission and calls. An ISDN multi-device connection can manage a maximum of 10 phone numbers nationwide, which can be transferred to all end devices as desired. The ISDN Telephone distinguishes a so-called service identification. Telephony, Fax, internet, and all other data transmissions can occur simultaneously without interfering with each other.

The connection types

The basic connection has two so-called user channels, which are each responsible for control information and data synchronisation. Both channels have a transmission rate of 64 kilobits per second. The control channel has a data transmission rate of 16 kilobits. The data synchronisation and the service occupy another 16 kilobits, thus the basic connection provides a total of 160 kilobits per second.

The primary multiplex connection has a total of 30 user channels, each with 64 kilobits per second and a control channel with 64 kilobits. Additionally, there is a channel for data synchronisation and system maintenance, also with 64 kilobits. The primary multiplex connection functions as a system connection. It is used for all ISDN telephone systems or fixed connections.

The advantages of ISDN

With the ISDN Telephone, you can make calls and surf the internet at the same time. The advantages are clear. The data transmission is digital, thus providing better voice quality. During phone calls, information about further incoming calls is conveyed. This function is referred to as "call waiting." There is also the possibility to block incoming calls and forward them to another telephone connection. This function is known as "call forwarding." Automatic callbacks are also possible, which then establish a direct participant connection. Additionally, channels for data transmission are available. These can also be linked if desired, thereby doubling the transmission capacity to 128 kilobits per second.

Summary of ISDN Telephone

• ISDN refers to an international standard for digital telecommunications networks
• digital transmission to the end device
• allocation of multiple phone numbers possible
• two types of connections
• multiple functions and channels
• simultaneous use of telephony and internet